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    <title>Document</title>
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    <script>
      var t = 80;
      var a = (5 / 9.0) * (t - 32) * 1000;
      var tmp = parseInt(a);
      var tempers = tmp / 1000;
      document.write("温度是" + tempers + "摄氏度");
    </script>
  </body>
</html>
